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Polymerization of 1,3-Butadiene with Catalysts Based on Cobalt Dichloride Complexes with Aminophosphines: Switching the Regioselectivity by Varying the MAO/Co Molar Ratio

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Chinese Journal of Polymer Science 2024年第4期42卷 501-510页

作者： Giovanni Ricci Anna Sommazzi Francesco Masi Alessandra Forni cnr-istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via A.Corti 1220133MilanoItaly Viale Giovanni XXIII 34 I-28100NovaraNOItaly Via Galvani 7 I-26866Sant’Angelo LodigianoLOItaly cnr-istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via C.Golgi 1920133MilanoItaly

Several novel cobalt dichloride complexes with amino-phosphine bidentate ligands were synthesized and *** some of them single crystals were obtained and their molecular structure was determined by X-ray diffraction *** the complexes were then used in combination with MAO for the polymerization of 1,3-butadiene,obtaining polymers with different structures(i.e.,predominantly 1,2 or cis-1,4)mainly depending on the type of ligand and on the MAO/Co molar *** behavior of these novel catalysts was compared with that exhibited,in the polymerization of the same monomer,by the systems CoCl_(2)(PR3)2-MAO and CoCl_(2)(PRPh2)2-MAO(R=alkyl or cycloalkyl group),and by the systems based on cobalt dichloride complexes with various bi-and tridentate ligands(e.g.,diphosphines,bis-imines,pyridyl-imines,bis-iminopyridines).The comparison between the different systems allowed us to make some clarity about the actual and effective role played by the various types of ligands in the polymerization of conjugated dienes with catalytic systems CoCl_(2)(L)-MAO,in which L=mono-,bi-,or tri-dentate ligand.

关键词： 1,3-Butadiene Stereospecific polymerization Cobalt catalysts Regioselectivity Aminophosphine ligands Crystal structures Chelate rings

Lower Continental Crusts Involved in the Alpine Orogeny:New Insight from the Santa Lucia Nappe Metasediments(Corsica,France)

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 904-920页

作者： Chiara FRASSI Maria DI ROSA Luca PANDOLFI Michele MARRONI Dipartimento di Scienze della Terra Universitàdi PisaVia Santa Maria 5356126 PisaItaly istituto di Geoscienze e Georisorse IGG-CNRVia Moruzzi50124 PisaItaly

In the Alpine Corsica(France),the Santa Lucia Nappe represents a peculiar unit preserving the unique relicts of Paleozoic lower to medium continental *** consists of composite basement affected by Permian granulite facies metamorphic conditions unconformably covered by a Late Cretaceous clastic sequence(Tomboni Conglomerate and Tralonca Flysch)affected by polyphase deformation and *** this work,we present a new reconstruction of the deformation events registered by the Tralonca Flysch during the Alpine *** D1 phase was testified by rare isoclinal *** D2 phase produced a continuous foliation and a map-scale sheath-fold with a top-to-W sense of *** D3 phase produced E-verging non-cylindrical folds and S3 crenulation cleavage that is not associated to metamorphic *** present the first temperature-pressure-deformation(P-T-d)path for the Tralonca Flysch,demonstrating that the Santa Lucia Nappe underwent accretion and then first stage exhumation in the Alpine wedge during the D1 phase with pressure and temperature peaks both occurred under blueschist metamorphic *** D2 phase occurred at lower pressure-temperature conditions during a second stage *** pressure-temperaturedeformation path is comparable with those of the Lower Units(i.e.,the subducted continental units of Alpine Corsica)suggesting a common geodynamic history.

关键词： blueschist-facies metamorphism P-T-d path Santa Lucia Nappe Corsica Alpine orogeny

Laser-optimized Pt-Y alloy nanoparticles embedded in Pt-Y oxide matrix for high stability and ORR electrocatalytic activity

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Journal of Energy Chemistry 2024年第5期92卷 508-520页

作者： Riccardo Brandiele Andrea Guadagnini Mattia Parnigotto Federico Pini Vito Coviello Denis Badocco Paolo Pastore Gian Andrea Rizzi Andrea Vittadini Daniel Forrer Vincenzo Amendola Christian Durante Department of Chemical Sciences University of PaduaVia Marzolo 135131 PadovaItaly istituto di Chimica della Materia Condensata e di Tecnologie per l’Energia ICMATE-cnr via Marzolo 1 I-35131 PadovaItaly

The development of active yet stable catalysts for oxygen reduction reaction(ORR)is still a major issue for the extensive permeation of fuel cells into everyday *** nanostructured Pt catalysts are to date the best available systems in terms of activity,the same is not true for stability,particularly under operating *** this work,Pt_(Х)Y alloy nanoparticles are proposed as active and durable electrocatalysts for ***_(Х)Y nanoalloys are synthesized and further optimized by laser ablation in liquid followed by laser fragmentation in *** novel integrated laser-assisted methodology succeeded in producing Pt_(Х)Y nanoparticles with the ideal size(1000 A g^(-1).At the same time,the nanoalloys are embedded in a fine Pt oxide matrix,which allows a greater stability of the catalyst than the commercial Pt reference,as directly verified on a gas diffusion electrode.

关键词： Electrocatalysis GDE ORR Pt_(2)Y Pt_(3)Y LAL LFL Oxide support Pto Nanoalloys

Metal-Halide Perovskite Submicrometer-Thick Films for Ultra-Stable Self-Powered Direct X-Ray Detectors

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Nano-Micro Letters 2024年第9期16卷 410-431页

作者： Marco Girolami Fabio Matteocci Sara Pettinato Valerio Serpente Eleonora Bolli Barbara Paci Amanda Generosi Stefano Salvatori Aldo Di Carlo Daniele M.Trucchi cnr‑ISM Consiglio Nazionale delle RicercheIstituto di Struttura della MateriaSede Secondaria di MontelibrettiDiaTHEMA LabStrada Provinciale 35D900010 MontelibrettiRomeItaly CHOSE–Centre for Hybrid and Organic Solar Energy Department of Electronic EngineeringUniversity of Rome“Tor Vergata”Via del Politecnico 100133 RomeItaly Faculty of Engineering Universita degli Studi Niccolo CusanoVia don Carlo Gnocchi 300166 RomeItaly SpecXLab CNR‑ISMConsiglio Nazionale Delle RicercheIstituto di Struttura Della MateriaArea della Ricerca di Tor VergataVia del Fosso del Cavaliere 10000133 RomeItaly

Metal-halide perovskites are revolutionizing the world of X-ray detectors,due to the development of sensitive,fast,and cost-effective ***-powered operation,ensuring portability and low power consumption,has also been recently demonstrated in both bulk materials and thin ***,the signal stability and repeatability under continuous X-ray exposure has only been tested up to a few hours,often reporting degradation of the detection *** it is shown that self-powered direct X-ray detectors,fabricated starting from a FAPbBr_(3)submicrometer-thick film deposition onto a mesoporous TiO_(2)scaffold,can withstand a 26-day uninterrupted X-ray exposure with negligible signal loss,demonstrating ultra-high operational stability and excellent *** structural modification is observed after irradiation with a total ionizing dose of almost 200 Gy,revealing an unexpectedly high radiation hardness for a metal-halide perovskite thin *** addition,trap-assisted photoconductive gain enabled the device to achieve a record bulk sensitivity of 7.28 C Gy^(−1)cm^(−3)at 0 V,an unprecedented value in the field of thin-film-based photoconductors and photodiodes for“hard”***,prototypal validation under the X-ray beam produced by a medical linear accelerator for cancer treatment is also introduced.

关键词： Metal-halide perovskite thin films Direct X-ray detectors Self-powered devices Operational stability Medical linear accelerator

Natural gas and biofuel as feedstock for hydrogen productionon Ni catalysts

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Journal of Natural Gas Chemistry 2009年第1期18卷 9-14页

作者： Pasquale Corbo Fortunato Migliardini istituto motori cnr Via Marconi 8-80125 Napoli Italy

In this article, the aptitude of natural gas as feedstock in steam reforming process for hydrogen production is compared with that of different liquid fuels （pure compounds and commercial fuels）, with the aim to investigate the potentialities of biofuels to overcome the CO2 emission problems deriving from fossil fuel processing. The performances of a nickel based catalyst （commercially used in steam reforming of natural gas） were evaluated in terms of feed conversion and yield to the different products as function of temperature, space velocity and water/fuel ratio. Furthermore, a preliminary evaluation of catalyst durability was effected by monitoring yield to H2 versus time on stream and measuring coke formation at the end of experimental tests. High yields to hydrogen were obtained with all fuels investigated, whereas the deactivation phenomena, which are correlated to carbon deposition on the catalyst, were observed with all tested fuels, except for methane and biofuel.

关键词： natural gas hydrogen steam reforming biofuels

The formation and growth mechanisms of young back-arc spreading ridges from high-resolution bathymetry:The Marsili Seamount(Tyrrhenian Sea,Italy)

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Geoscience Frontiers 2024年第1期15卷 325-338页

作者： Eugenio Nicotra Salvatore Passaro Guido Ventura Dipartimento di Biologia Ecologia e Scienze della Terra Universitàdella Calabria87036 Arcavacata di RendeCosenzaItaly istituto di Scienze Marine cnr 80133 NapoliItaly istituto Nazionale di Geofisica e Vulcanologia 00143 RomaItaly istituto per lo Studio degli impatti Antropici e Sostenibilitáin ambiente marino cnr 91026 Capo GranitolaTrapaniItaly

The formation and growth mechanisms of Mid-Ocean Ridges(MOR)are relatively well known,whereas those of back-arc spreading ridges are comparatively less known because geophysical,geochemical,and morphological data are scarce and of low *** we present a high-resolution bathymetry of the Marsili Seamount(MS;1 Ma-3 ka),which represents the inflated spreading ridge of the 2 Ma old Marsili back-arc basin associated to the subduction of the Ionian Sea below the Calabrian Arc and Tyrrhenian *** is 70 km long,30 km wide,and its height reaches about 3000 m from surrounding *** new digital bathymetric model has a 5 m grid cell size resolution and covers the MS bathymetry from-1670 mbsl to the top at-491 *** conduct morphometric and morphological analyses of the bathymetry and recognize landforms due to volcanic,tectonic,hydrothermal and gravity *** consists of volcanoes related to fissural and central-type activity,this latter located at the northern and southern tips of the main dike *** swarms represent the surface expression of different ridge segments whose strikes are controlled by the larger scale back-arc spreading processes and by the local occurrence of an active hydrothermal *** latter develops in a flat area between two partly overlapping ridge segments where historical volcanism and extensional processes *** ridges represent the embryonic stage of the formation of transform-like *** volcanoes,the northern of which is characterized by a caldera,form at the tips of MS because the decrease in width of the major volcanic fissures promotes vent localization associated with the formation of sill-like reservoirs from which central-type vents may *** processes affecting the MS flanks are due to shallow seafloor *** collapses affecting the northernmost central-type polygenic volcano must be included in the evaluation of the hazard related to potential *** dipping faul

关键词： Back-arc spreading ridge Morphology Tectonics Volcanism Marsili seamount

A novel 2D-GO@WS2 electrochemical platform for the determination of thiram fungicide

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Journal of Environmental Sciences 2024年第2期136卷 226-236页

作者： Khouloud Abid Daniela Iannazzo Consuelo Celesti Amani Khaskhoussi Antonino Foti Ramzi Maalej Pietro Giuseppe Gucciardi Giovanni Neri Department of Engineering University of MessinaC.da Di DioI-98166 MessinaItaly INSTM Research Unity of MessinaItaly Laboratory of Dielectric and Photonic Materials Faculty of Sciences of SfaxSfaxUniversitySfax 3018Tunisia cnr IPCF istituto per i Processi Chimico-Fisici viale F.Stagno D’Alcontres 37I-98156 MessinaItaly

In this paper,the determination of Thiram fungicide by a novel modified screen-printed carbon electrode(SPCE)fabricated modifying the working electrode(WE)with 2D-GO/WS2nanohybrid composites,is *** electron microscopy(SEM),Raman spectroscopy,and fluorescence analysis(PL)were used to reveal the morphological and microstructural characteristics of the 2D-GO/WS2 nanohybrids with different graphene oxide:tungsten disulphide(GO:WS_(2))*** characterization demonstrated that the 2D-WS2/GO nanohybrids having a GO:WS_(2)ratio=2:1 shows the highest electrocatalytic activity towards oxidation of *** developed sensor permits the quantification of Thiram in the linear range 0.083-0.33μM with a limit of detection(LOD)of 0.02μM,which is below the legal limits for this fungicide in drinking water or foods.

关键词： WS_(2)nanosheets Graphene Oxide(GO) Electrochemical sensor Fungicides Thiram

Gate-controlled supercurrent effect in dry-etched Dayem bridges of non-centrosymmetric niobium rhenium

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Nano Research 2024年第7期17卷 6575-6581页

作者： Jennifer Koch Carla Cirillo Sebastiano Battisti Leon Ruf Zahra Makhdoumi Kakhaki Alessandro Paghi Armen Gulian Serafim Teknowijoyo Giorgio De Simoni Francesco Giazotto Carmine Attanasio Elke Scheer Angelo Di Bernardo Department of Physics University of KonstanzUniversitätsstraße 1078464 KonstanzGermany cnr-Spin c/o Universitàdegli Studi di Salernovia Giovanni Paolo II 13284084 Fisciano(SA)Italy NEST Istituto Nanoscienze-CNR and Scuola Normale SuperiorePiazza San Silvestro 1256127 PisaItaly Dipartimento di Fisica“E.R.Caianiello” Universitàdegli Studi di SalernoVia Giovanni Paolo II 13284084 Fisciano(SA)Italy Advanced Physics Laboratory Institute for Quantum StudiesChapman UniversityBurtonsvilleMD 20866USA

The application of a gate voltage to control the superconducting current flowing through a nanoscale superconducting constriction,named as gate-controlled supercurrent(GCS),has raised great interest for fundamental and technological *** gain a deeper understanding of this effect and develop superconducting technologies based on it,the material and physical parameters crucial for the GCS effect must be ***-down fabrication protocols should also be optimized to increase device scalability,although studies suggest that top-down fabricated devices are more resilient to show a ***,we investigate gated superconducting nanobridges made with a top-down fabrication process from thin films of the noncentrosymmetric superconductor niobium rhenium with varying ratios of the constituents(NbRe).Unlike other devices previously reported and made with a top-down approach,our NbRe devices systematically exhibit a GCS effect when they were fabricated from NbRe thin films with small grain size and etched in specific *** observations pave the way for the realization of top-down-made GCS devices with high *** results also imply that physical parameters like structural disorder and surface physical properties of the nanobridges,which can be in turn modified by the fabrication process,are crucial for a GCS observation,providing therefore also important insights into the physics underlying the GCS effect.

关键词： superconductivity non-centrosymmetric superconductors superconducting devices gated devices gate-controlled supercurrent top-down fabrication

Application of a Robust Model Reference Adaptive Control Algorithm to a Nonlinear Automotive Actuator

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International Journal of Automation and computing 2014年第4期11卷 377-391页

作者： Alessandro di Gaeta Umberto Montanaro istituto motori National Research Council Naples Italy

Model reference adaptive control is a viable control method to impose the demanded dynamics on plants whose parameters are affected by large uncertainty. In this paper, we show by means of experiments that robust adaptive methods can effectively face nonlinearities that are common to many automotive electromechanical devices. We consider here, as a representative case study, the control of a strongly nonlinear automotive actuator. The experimental results confirm the effectiveness of the method to cope with unmodeled nonlinear terms and unknown parameters. In addition, the engineering performance indexes computed on experimental data clearly show that the robust adaptive strategy provides better performance compared with those given by a classical model-based control solution with fixed gains.

关键词： Model reference adaptive control robust adaptive control nonlinear systems automotive control electronic throttle body electromechanical actuators